Shaker-screen



(No Model.)

D. E. PHILLIPS. SHAKER SCREEN.

No. 555,262. Patented Feb, 25, 1896..

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W JM 7 7 UNITED STATES PATENT OFFICE.

DAVID E. PHILLIPS, OF MAI-IANOY CITY, PENNSYLVANIA.

SHAKER-SCREEN.

SPECIFICATION forming part of Letters Patent NO. 555,262, dated February 25, 1896.

Applicati fil d July 25,1895. Serial No. 557,118. (No model.)

To aZZ whom it may concern:

Be it known that 1, DAVID E. PHILLIPS, of Mahanoy City, county of Schuylkill, State of Pennsylvania, have invented an Improvement in Shaker-Screens, of which the following description, in connection with the accompanyin g drawings, is a specification, like letters and figures on the drawings representing like parts.

This invention relates to that class of screens commonly termed shaking or shaker screens in contradistinction to rotary or revoluble screens. In the latter class it is obvious that only a small portion of the sc reenin g-surface is operative at any one time, the remainder of the screen being superfluous, and the coal or other material to be screened is thrown together along the lowest portion of the screen as the latter revolves.

The shaker-screen is in manyrespects more economical, for the greater part of the screening-surface is utilized at all times, and being flat the material is not thrown together in a heavy mass, but it is spread more or less evenly in a comparatively thin layer over the entire screening-surface.

The great objection to a shaker-screen is due to the great strain put upon its supports, as the reciprocating movement imparted to the screen is very severe, about one hundred and thirty-five strokes per minute being the least with which good results can be obtained. Inasmuch as the weights of such screens vary from nine hundred to twelve hundred pounds it is obvious that the strain upon the supporting structure must be great and mainly in a horizontal direction, as the vibrating movement of the screen is usually attained by suitably connecting it with a rotating shaft provided with one or more cams. This horizontal alternating pull and push on the screenhouse wrenches it and damages it, as well as the various shaft-bearings, getting them out of true and requiring constant repairs.

My present invention has for its object the production of a shaker-screen which obviates the foregoing objections in a simple and eflicient manner, whereby the life of the screen apparatus is greatly prolonged and the cost of repairs reduced, and the power necessary to operate the screen is reduced.

Figure 1 of the drawings represents, in perspective, a shaker-screen apparatus embodying my invention; and Fig. 2 is a detail view, also in perspective, of a modification of the screenhanger, to be described.

Referrin g to Fig. 1, the supporting-frame is composed of uprights a and top and bottom side timbers b and b, the top timbers, b, being connected by suitable cross-braces b the whole structure being built in or forming a part of the screen house or building. J ournal boxesor bearings c, secured to the top pieces, I), support the main shaft 0', shown as provided with a pulley 0 by which rotation is transmitted to the main shaft 0 from any suitable source of power. (Not shown.) Bearings d on the top timbers support the journals d of a rock-shaft (1 having securely bolted thereto arocker-arin (Z forked at its outer end at d to provide bearings for a slideblock d movable in the fork in the direction of the length of the rocker-arm.

The slide-block d has an opening therein to receive a cam disk or eccentric 0 fast on the main shaft, whereby the rotation of the latter imparts to the arm d an up-and-down rocking motion, it in turn rocking the shaft (Z the arm d also acting with a long leverage upon the rock-shaft.

Hangers e securely bolted to the rock-shaft d and depending therefrom have bearings c at or near their lower ends for a cross-bar 6 to which is bolted, as at 10, the screen S, shown as rectangular in shape and provided With longitudinal upturned side flanges S, the screen being inclined downwardly from the feed end. (Shown in Fig. 1 at the left-hand end of the apparatus.)

By the rocking motion of the rock-shaft d a longitudinal vibration is imparted to the screen S by means of the rigid hangers e, the cross-bar 6 moving in its bearings to prevent twisting or cramping of the screen as it is vibrated.

To give a vertical vibration to the screen I have suspended it from the main shaft cby hangers f, provided with seats or bearings for cam disks or eccentrics e' fast on the main shaft, the screen resting upon but not being secured to a cross-bar f, preferably mounted in bearin gs f in the hangers near their lower ends. As the main shaft rotates, the cam 0 acts to vibrate the screen S longitudinally with a series of short quick strokes, and at the same time the cams e vibrate or shake the screen up and down.

I prefer to suspend the receiving end of the screen, and thisis accomplished by means of a yoke f pivoted at f to the adjacent cross-brace b the ends of the yoke beingconnected to the screen by chains f or by other suitable flexible connections.

The coal or other material to be screened is fed to the upper end of the screen by a suitable chute G, and as it passes down over the screen S it is thoroughly agitated and separated by the double vibration imparted to the screen, so that it is rapidly and properly screened, the refuse, or the portions too large to pass through the openings in the screen-plate, passing off from the lower end of the plate.

The flanges S prevent the material from passing over the sides of the screen, and direct the material over the screening-surface.

It will be obvious that by my construction herein described I obviate the severe horizontal strains on the supports, the main strains being exerted in a vertical direction and thus carried to the foundations of the screen-house in the direction of the greatest resistance, instead of in the direction of least resistance, as heretofore.

By setting the cams or eccentrics c opposite to each other on the shaft c one side of the screen will be lifted as the other is depressed, and vice versa.

In Fig. 1, I have shown a single screenplate S, but a plurality of screen-plates may be employed by simply extending the hangers and providing them with cross-bars for the additional screen-plates, as in Fig. 2. One of the hangers, as h, is partly shown provided with bearings m and n for their respective cross-bars m and 02 the latter supporting each a screen-plate, as S and S one above the other, and as many screens may be used as desired, it being understood that the front and back hangers will be provided with a like number of cross-bars, corresponding to the number of screen-plates to be used.

My invention is not restricted to the precise construction and arrangement herein shown, as the same may be modified i various particulars without departing from the spirit and scope of my invention.

I claim 1. In a screening apparatus, a rock-shaft, means to rock it, hangers rigidly secured to said rock-shaft, a screen-plate connected near one end to said hangers, to be reciprocated longitudinally, vertically-movable supports for the other end of the screen-plate, and

means to move them, to thereby impart to the screen-plate a compound vertical and horizontal vibration, said compound motion being more violent at the receiving end of the screen, substantially as described.

.2. In a screening apparatus, a screen-plate, depending hangers to which it is connected near one end, means to swing the hangers from their upper ends as pivots to reciprocate the screen-plate longitudinally, a rotatable shaft, eccentrics thereon, and depending hangers in engagement with said eccentrics and supporting the other end of the screen, rotation of the shaft moving the said hangers longitudinally to vibrate the screenplate vertically, substantially as described.

3. In a screening apparatus, a screen-plate, independent hangers to support the plate near its ends, a rock-shaft to which one set of hangers is rigidly secured, whereby longitudinal reciprocation is imparted to the plate,

a rotatable shaft from which the other set of hangers depend, connections between it and the rock-shaft, to rock the latter, and cams on the rotatable shaft to raise and lower the hangers thereon, to vibrate the screen-plate vertically, substantially as described.

it. In a screening apparatus, a rock-shaft, a rotating shaft, cams thereon, connections between said shafts to rock the rock-shaft, rigid hangers fast on and depending from the rock-shaft, hangers eccentricallymounted on the rotating shaft, and a screen plate sus pended by the hangers, vibrated longitudinally and vertically by the rotation of the cam-shaft, substantially as described.

5. In a screening apparatus, a screen longitudinally inclined, a rock-shaft provided at either end with depending hangers rigidly fixed thereon and pivotally supporting the lower end of said screen at their vibrating ends, a shaft provided with a plurality of cams, an arm fixed at one end to said rockshaft in axial alignment therewith and provided at its opposite end with a forked portion arranged to be moved vertically by positive engagement with one of said cams, and another set of hangers supported at their upper ends on said cams, and arranged in pivotal connection at their lower ends with the higher portion of said screen, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

DAYID E. PHILLIPS. \Vitnesses:

JosEPH G. llIORGAN, GEORGE BRITZ. 

